Process for the optical brightening of organic materials

ABSTRACT

The present invention relates to a process for the optical brightening of organic materials using compounds of the formula   IN WHICH A REPRESENTS HYDROGEN, HALOGEN, THE METHYL GROUP OR THE METHOXY GROUP, Z1 and/or Z2 denotes a ring member CH- or N- and Alpha represents a hydrogen atom, a phenyl residue or a residue of the series   IN WHICH (I) at least one residue Alpha differs from hydrogen or phenyl and has the significance of one of the other residues quoted for Alpha , and in which (II) terminal phenyl or naphthyl residues may contain alkyl, halogen or alkoxy groups. These new compounds represent valuable optical brightening agents.

United States Patent 1191 Slegrist et al.

[ Nov. 19, 1974 PROCESS FOR THE OPTICAL BRIGHTENING OF ORGANIC MATERIALS[75] Inventors: Adolf Emil Siegrist, Basel; Peter Liechti, Binningen;Erwin Maeder, Aesch/BL; Leonardo Guglielmetti, Birsfelden; Hans RudolfMeyer; Kurt Weber, both of Basel, all of Switzerland [73] Assignee:Ciba-Geigy AG, Basel, Switzerland [22] Filed: Oct. 5, 1972 [21] Appl.No.: 295,405

Related US. Application Data [60] Division of Ser. No. 67,967, Aug. 28,1970, Pat. No. 3,758,462, which is a continuation-in-part of Ser. No.588,318, Oct. 21, 1966, abandoned.

[30] Foreign Application Priority Data Oct. 28, 1965 Switzerland14902/65 July 4, 1966 Switzerland 9649/66 52 us. (:1 117/335 T, 117/3331117/1388 F, 96/1.5, 96/1.6, 96/87, 252/5012 w 51 1m. 01. D06p 5766,669623/00 58 Field of Search 117/335 T; 252/3012 w; 96/15, 1.6, 87

[56] References Cited UNITED STATES PATENTS 11/1967 Siegrist et all17/33.5 T

12/1970 Siegrist et a1 117/335 T 2/1972 Siegrist et al. 252/3012 W OTHERPUBLICATIONS Primary Examiner-William D. Martin AssistantExaminerWi1liam R. Trenor Attorney, Agent, or Firm-Joseph G. Kolodny [57] ABSTRACT The present invention relates to a process for the opticalbrightening of organic materials using compounds of the formula in whicha represents hydrogen, halogen, the methyl group or the methoxy group, Zand/or Z denotes a ring member =Cl-l or =N-- and a represents a hydrogenatom, a phenyl residue or a residue of the senes in which (1) at leastone residue 01 differs from hydrogen or phenyl and has the significanceof one of the other residues quoted for a, and in which (1]) terminalphenyl or naphthyl residues may contain alkyl, halogen or alkoxy groups.These new compounds represent valuable optical brightening agents.

8 Claims, No Drawings PROCESS FOR THE OPTICAL BRIGHTENING OF ORGANICMATERIALS CROSS-REFERENCE TO RELATED APPLICATION This application is adivision of copending application Ser. No. 67,967, filed Aug. 28, 1970(now US. Pat. No. 3,758,462) which is, in turn, a continuationin-part ofcopending application Ser. No. 588,318, filed Oct. 21, 1966 (nowabandoned).

SUMMARY OF THE DISCLOSURE in which a represents hydrogen, halogen, themethyl group or the methoxy group, Z and/or Z denotes a ring member =CH-or =N- and or represents a hydrogen atom a phenyl residue or a residueof the series in which (I) at least one residue a differs from hydrogenor phenyl and has the significance of one of the other residues quotedfor a, and in which (II) terminal phenyl or naphthyl residues mayadditionally contain 1 to 3 alkyl groups 1 to 2 halogen atoms, an alkoxygroup, a carboxylic acid group, a carboxylic acid ester group or acarboxylic acid amide group. In the process for optical brightening oforganic materials the said new compounds are incorporated with thematerials to be optically brightened or are applied to the surfacethereof. The compounds according to the invention may be s-triazinederivatives, and within this class there are to be mentioned ascompounds of special value those which corresponds to the formula:

in which R' denotes an organic residue bonded to the triazine lsbxvmeenss f b nzsys r s, R; a benzene residue bonded in the 1,4-positionto the triazine ring and the -CH= group, and R an aromatic residue.

Of outstanding importance within the scope of the above formula aretriazine derivatives of the formula in which B, represents a phenyl ordiphenyl residue and B represents hydrogen, a phenyl residue or an alkylgroup having I to 4 carbon atoms, and in which terminal phenyl residuesmay contain an alkyl group with l to 4 carbon atoms, halogen or amethoxy group.

Interesting compounds of the triazine series can also be represented bythe formula in which A denotes a residue of the series A denotes aphenyl, diphenylyl or naphthyl residue or a residue A and these ,quotedaromatic residues may additionally contain 1 to 2 substituents X havingthe significance of hydrogen, alkyl or halogen, preferably in thephenylene nuclei described under A The general formula (1) comprisespyridine and pyrimidine derivatives; of the pyridine derivatives specialmention is deserved by those which correspond to'the formula in which Wdenotes a phenyl, diphenyl, l-naphthyl or Z-naphthyl residue.

In these formulae quoted under numbers (1) to (6) possible alkyl groupsin principle also include long chain alkyl groups, but in practice it ismostly alkyl groups containing up to about 8 carbon atoms, preferably lto 4 carbon atoms, and especially branched-chain alkyl groups, whichrequire consideration.

Though again in the case of alkoxy groups higher members, that is to saythose containing 4 or more carbon atoms, as well as polyalkyleneoxygroups, are possible, the predominant practical significance resides inalkoxy groups containing 1 to 4 carbon atoms. Amongst the halogensquoted, chlorine is of especial interest. While in the case of thecarboxylic acid ester groups, theoretically all esterifying componentsare possible, in most cases only alkyl esters having 1 to 18 carbonatoms and the benzyl ester are of interest. The carboxylic acid amidegroups may be free or monoor disubstituted in any desired manner. Amongthe substituted representatives the alkylamides and arylamides having upto 18 carbon atoms as well as cyclic amides (for example of themorpholide type) are the most important. The term free acids here ofcourse also comprises salts thereof.

In principle, the compounds defined above which according to thisinvention are to be used for optical brightening processes can beprepared by different methods.

A particularly advantageous process for the manufacture of compounds ofthe formula (1 consists in reacting a compound of the formula in whichthe symbols a, Z and 2, have the meanings given above, and the symbol-1r i-crn means that this place may be occupied by a hydrogen atom or amethyl group and that at least one methyl group must be present in themolecule, in the presence of a strong basic alkali compound with aSchiffs base, the reaction medium being a strongly polar, neutral tobasic organic solvent which (I) is free from atoms especially hydrogenatoms that can be replaced by alkali metal, and (II) is practicallyanhydrous, and if an alkali hydroxide is used as strongly basic alkalicompound, such alkali hydroxide may have a water content of up to 25percent.

As starting materials according to the above formula (7) there may beused, for example: A. Compounds of formula in which R denotes, forexample, a monocyclic benzene residue and X a hydrogen atom, a chlorineatom, a methoxy group or a methyl group.

B. Compounds of the formula o l 1 X2 in which X X X X and X denotemethyl groups or hydrogen atoms. C. Compounds of the formulae l-Qr rQ- HC- H, CH;

-Q Qi In the above formulae 1. terminal phenyl radicals may containadditional substituents of the series alkyl (especially with l to 4carbon atoms), halogen (especially chlorine) or alkoxy (especially withl to 4 carbon atoms) 2. phenyl radicals on s-triazine rings mayadditionally contain methyl groups; moreover, the symbol daotes thateither a hydrogen atom or a methyl group,

H which Ar denotes an aromatic residue. ln

one or both of the components required for the synthesis of the Schiffbases (aldehyde and amine) may con- 40 tain further substituents,provided the above restriction is observed. Since the amine, especiallyaniline, residue is split off during the reaction and is no longerpresent in the final product, the presence of substituents in this isgenerally not indicated and is uninteresting. Nevertheless substituentswhich do not interfere with, or hinder, the reaction, for examplechorine atoms, may be present in this ring also. Preferred interestattaches to Schiff bases of aromatic aldehydes with anilines, that is tosay aromatic aldehyde-anils. Such anils for example correspond to theformula in which k and I may be identical or different and denotehydrogen atoms, chlorine atoms or methoxy groups and in which hrepresents chlorine or, preferably, hydrogen. Adjacent k and I maytogether also form a -OCl-l O group. Another important variant ofaromatic anils corresponds to the formula in which h (as above)represents a hydrogen atom or chlorine and Ar' denotes a naphthyl ordiphenyl residue. As monoaldehydes ,suitable for the synthesis of theseSchiff bases there may be quoted for example: aldehydes of the benzeneseries such as benzaldehyde or its halogenated analogues, such as themonochloroanalogues and dichloro-analogues, alkoxybenzaldehydes such asp-methoxy-benzaldehyde, alkylated benzaldehydes, provided these do notcontain any pmethyl groups, such as toluyl-aldehyde, xylyl-aldehyde andcumoyl-aldehyde, methylenedioxy-benzaldehyde (piperonal),4-dimethylamino-benzaldehyde, 4-diethylamino-benzaldehyde, anddiphenyl-aldehyde; aldehydes of the naphthalene series such as aand,B-naphthaldehyde.

Compounds of formula (7) are reacted with the aldehydeanils in thepresence of a strongly polar, neutral to alkaline, organic solvent whichis free of atoms, especially hydrogen atoms, which are replaceable byalkali metals. Such solvents are especially represented by di-alkylatedacylamides, preferably those of the type in which Alkyl denotes a loweralkyl group (containing 1 to 4 carbon atoms), especially a methyl group,Acyl the residue of a low carboxylic acid (containing 1 to 4 carbonatoms), especially formic acid or acetic acid, or of phosphoric acid,and w gives the basicity of the acid. As important examples of suchsolvents there may be quoted dimethylformamide, diethylformamide,dimethylacetamide and hexamethyl-phosphoric acidtriamide. It is alsopossible to use solvent mixtures.

The reaction furthermore requires a strongly basic alkali compound. Bythe term strongly basic alkali compounds there are to be understood,within the framework of the present invention, such compounds of thealkali metals (1. main group of the periodic table of elements)including ammonium as have a basic strength of at least about that oflithium hydroxide, Accordingly, they may be compounds of lithium,sodium, potassium, rubidium, caesium or ammonium of, for example, thealcoholate, hydroxide, amide, hydride, sulphide or strongly basic ionexchanger types. Potassium compounds of composition in which m denotesan integer of l to 6, such as forexample potassium hydroxide orpotassium tertiarybutylate, are advantageously used(above all when mildreaction conditions as regards reaction temperature appear to beindicated). In the case of alkali alcoholates and alkali amides (andhydrides) it is here necessary to work in a practically anyhydrousmedium, whereas in the case of alkali hydroxides water contents of up to25 percent (for example contents of water of crystallisation) areadmissible. In the case of potassium hydroxide a water content of up toabout 10 percent has proved appropriate. As examples of other alkalicompounds which may be used there may be quoted sodium methylate, sodiumhydroxide, sodium amide, lithium amide, lithium hydroxide, rubidiumhydroxide, caesium hydroxide and the like. Of course it is also possibleto work with mixtures of such bases.

It is appropriate to react the compounds of formula (7) with thealdehyde-anils in equivalent amounts, so that no component is present insignificant excess. As regards the alkali compound, it is advantageousto use at least the equivalent amount, that is to say at least 1 mole,of a compound having, for example, a KO group, per mole ofaldehyde-anil. When using potassium hydroxide a four-fold to eight-foldamount is preferably employed.

The reaction of the invention may generally be carried out attemperatures in the range of between about and 150C. lf alcoholates areused as the potassium compound in the reaction, then the application ofheat is generally not necessary. The procedure is, for example, that thealdehyde-aniline is added to the mixture of the compound of formula (7),the solvent and the potassium alcoholate, preferably with stirring andwith exclusion of air, at a temperature of between and 30C, whereuponthe reaction takes place of its own accord, with a slight temperaturerise. When using potassium hydroxide it is frequently necessary to workat higher temperatures. For example the reaction mixture is slowlywarmed to 30 100C and then kept at this temperature for some time, forexample to 2 hours. The products may be worked up from the reactionmixture by usual methods which are in themselves known. Another processfor the manufacture of such new triazinylstilbene compounds essentiallyconsists in reacting in an anhydrous medium with the aid of Friedel-Crafts catalysts, such as aluminium chloride or better yet aluminiumchloride and thionyl chloride in the molecular ratio of 1:2,stilbene-4-carboxylic acid halides, especially chlorides, if desired inthe presence of inert non-polar to slightly polar organic solvents, asfor example ortho-dichlorobenzene or tetrachlorethylene at a temperaturenear the boiling point of the reaction mixture, that is to say, at about70 to 130C, with corresponding aromatic nitriles R"'-C N (R as definedabove) [cf. Berichte 89,223 (1956)]. It is of advantage to use an excessof aromatic nitrile which at the same time serves as solvent. Theintemiediate products formed, if desired after being isolated, aretreated, at a temperature of about 30 to 130C (with ammonium chloride[cf. J. Chem. Soc. 1941, pages 278 to 282] or more advantageously withgaseous ammonia. The reaction sequence may be illus trated schematicallyfor example for the manufacture of new compounds of the formula (2) asfollows:

II N l anhydrous REL The new optical brighteners of the compositiondescribed above possess a more or less pronounced fluorescene in thedissolved or finely divided state. They are suitable for opticalbrightening of the most diverse organic materials of high or lowmolecular weight or of materials containing such organic substances.

As such materials there may for example be quoted the following group oforganic materials, without the recital which follows in any way beingintended to express any limitation in this respect:

1. Synthetic organic high molecular materials such as (a) polymerisationproducts based on organic compounds containing at least onepolymerisable carboncarbon double bond (homopolymers or copolymers aswell as their post-treatment products such as crosslinking products,graft products or degradation products, polymer dilutions and the like)as examples of which there may be quoted: polymers based ona,B-unsaturated carboxylic acids, especially acrylic compounds, (as forexample acrylic esters, acrylic acids, acrylonitrile, acrylamides andtheir derivatives or their methacryl analogues), olefine hydrocarbons asfor example ethylene, propylene, isobutylene, styrenes, dienes, asespecially butadiene, isoprene, that is to say, also rubbus andrubber-like polymers, furthermore socalled ABS-polymers), polymers basedon vinyl and vinylidene compounds (as for example vinyl esters, vinylchloride, vinyl sulfonic acid, vinyl ether, vinyl alcohol, vinylidenechloride, vinyl carbazole) of halogenated hydrocarbons (chloroprene,highly halogenated ethylenes), of unsaturated aldehydes and ketones (forexample acroleine, etc.), of allyl compounds, etc., graft polymerizationproducts (for example by grafting on vinyl monomers), cross-linkingproducts (for example by means of dior polyfunctional cross-linkingagents such as divinylbenzene, polyfunctional allyl compounds orbis-acryl compounds or by partial degradation (hydrolysis,de-polymerization) or modification products as are obtainable bymodification of reactive groupings (for example esterification,etherification, halogenation, auto-cross-linking).

b. Other polymerization products, as are obtainable for example by ringopening, for example, polyarnides of the polycaprolactam type, alsoformaldehyde polymers as well as polymers that are accessible both bypolyaddition and polycondensation, such as polyethers, polythioethers,polyacetals, thioplasts.

c. polycondensation products or precondensates based on diorpolyfunctional compounds with condensable groups, their homoandco-condensation products as well as aftentreatment products, examples ofwhich are:

Polyesters that are saturated (for example polyethylene terephthalate)or unsaturated (for example maleic aciddialcohol polycondensates andtheir cross-linking products with vinylmonomers that can becopolymerized, or that are linear or branched (including those based onpolyhydric alcohols, as for example alkyl resins);

Polyamides (for example hexamethylene diamine adipate), maleinateresins, melamine resins, phenol resins, furan resins, carbamide resinsor their precondensates and similarly built products, polycarbonates,silicon resins and others.

d. Polyaddition products, such as polyurethanes (cross-linked and notcross-linked), epoxide resins.

II. Semisynthetic organic materials as for example 9 cellulose esters ormixed esters (acetale, propion etc.), nitrocellulose, cellulose ethers,regenerated cellulose (oiscose, cuprammonium cellulose) or theiraftertreatment products, casein plastics.

Ill. Natural organic materials of animal or vegetable origin, forexample based on cellulose or on proteins such as wool, cotton, silk,raffia, jute, hemp,.pelts, hair, leather, wood compositions in a finelydevided form, natural resins (such as colophony, especially lacquerresin), and furthermore rubber, guttapercha, balata as well as theirpost-treatment products and modification products (for example bycuring, cross-linking or grafting), degradation products (for example byhydrolysis, de-polymerization), products obtainable by modification ofreactive groups (for example by acylation, halogenation, cross-linking,etc.). p H

The organic materials requiring consideration may be present in the mostdiverse processing states (raw materials, semi-finished goods orfinished goods) and states of aggregation. They may thus be present inthe form of the most diverse shaped articles, for example, predominantlythree-dimensional bodies, such as blocks, tablets, profiles, tubes,injection mouldings or the most diverse working pieces, chips, granules,and foams; predominantly two-dimensional bodies, such as films, foils,lacquers, strips, coverings, impregnations and coatings, orpredominantly one-dimensional bodies, such as filaments, fibers, flocks,bristles, and wires. The materials quoted may on the other hand also bepresent in an unshaped state in the most diverse homogeneous andinhomogeneous forms of distribution and states of aggregation, forexample as powders, solutions, emulsions, dispersions, latices(examples: lacquer solutions, polymer dispersions), sols, gels, putties,pastes, waxes, adhesives and trowelling compositions and the like. Fibrematerials may for example be present as continuous filaments, staplefibres, flocks, hanks, yarns, threads, fibre fleeces, felts, waddings,flocked structures, woven textile fabrics or laminates, knitted fabricsas well as papers, cardboards or paper compositions and the like. Thecompounds to be used according to this invention are important also forthe treatment of organic textile material, especially fabrics. Thebrightening according to this invention of fibers which as staple fibersor monofils may be in the form of hanks, fabrics, knitted goods,fleeces, flocked substrates or textile laminates is advantageouslyperformed in an aqueous medium which contains the compound concerned ina finely divided state (suspension or solutions.) If necessary, adispersant may be added during the treatment, as for example soap, apolyglycol ether of a fatty alcohol, a fatty amine or an alkylphenol,sulfite cellulose waste liquor or a condensation product of anoptionally alkylated naphthalene sulfonic acid with formaldehyde.Working in a neutral, slightly alkaline or acid bath has providedespecially advantageous. It is also of advantage to perform thetreatment at a temperature of about 50 to 100C, for example at theboiling temperature of the bath or near it (about 90C). For theprocessing according to this invention solutions in organic solvents canalso be used. When used as brighteners, these compounds may be added tothe materials quoted either before or during shaping. Thus for examplethey may be added to the moulding composition in the manufacture offilms. foils, tapes, or other moulded articles, or they may bedissolved, dispersed or otherwise finely divided in the spinningcomposition before spinning. The optical brighteners may also be addedto ,the starting substances, reaction mixtures or intermediate productsfor the manufacture of fully synthetic or semi-synthetic organicmaterials, that is tosay also;before or during the chemical reaction,for exampleinthe case of a polycondensation (thus also toprecondensates), a polymerisation (thus also to prepolymers) or apolyaddition. The new optical brighteners may of course also be employedin all cases where organic materials of the type indicated above arecombined with inorganic materials in any form. (Typical Examples:detergents, white pigments in organic substances). They aredistinguished by exceptionally good heat stability, light fastness andresistance to migration. The amount of the new optical brighteners to beused, relative to the material to be optically brightened, may varywithin wide limits. A clear and durable effect can already be achievedwith very small amounts, in some cases for example with amounts of 0.001percent by weight. However amounts of up to about 0.5 percent by weightand more may also be used. For most practical purposes amounts ofbetween 0.01 and 0.2 percent by weight are preferably of interest.

The compounds serving as brighteners may for example also be employed asfollows: a. mixed with dyestuffs or pigments or as an additive to dyebaths, printing, etching or reserve pastes. Further also for thepost-treatment of dyeings, prints or discharge prints; b. mixed withso-called carriers," antioxidants, light protection agents, heatstabilisers, chemical bleaching agents or as an additive to bleachingbaths; 0. mixed with cross-linking agents, finishing materials such asstarch or synthetically produced finishes. The products of thisinvention can with advantagealso be added to liquors used to produceanit-crease dressings; d. in combination with detergents, where thedetergent and the brightener may be separately added to the wash bathsto be used, or preferably detergents are used which contain thebrightener mixed into them; suitable detergents are for example soaps,salts of sulfonate washing agents, as for example salts of sulfonatedbenzimidazoles substituted on the 2-carbon atom by higher alkylradicals, also salts of monocarboxylic acid esters of 4-sulfophthalicacid with higher fatty alcohols, furthermore salts of fattyalcohol-sulfonates, alkylarylsulfonic acids or condensation products ofhigher fatty acids with aliphatic hydroxyor aminosulfonic acids; It isalso possible to use non-ionic detergents, for example polyglycol ethersderived from ethylene oxide and higher fatty alcohols, alkyl phenols orfatty amines; e. in combination with polymeric carriers (polymerization,polycondensation or polyaddition products), in which the brighteners areoptionally introduced along with other substances in a dissolved ordispersed form, for example in the case of coating, impregnating orbinding agents (solutions, dispersions, emulsions) for textiles,fleeces, paper, leather. f. as additives to the most diverse industrialproducts in order to make these more marketable or to avoiddisadvantages in their usability, for example as an additive to glues,adhesives, paints and the like.

The compounds of the formula first above shown may also be used asscintillators for various photographic purposes, such as forelectrophotographic reproduction or for supersensitisation.

When the brightening process is combined with other treatments orprocessing methods, the treatment is advantageously performed with theuse of corresponding stable preparations. Such preparations arecharacterized by a content of an optical brightener of the generalformula shown at the beginning and also a dispersant, a detergent, acarrier, a dyestuff, a pigment or a dressing agent.

The treatment of a number of fibrous substrates, for example polyesterfibers, with the brighteners of this invention advantageously consistsin impregnating these fibers with an aqueous dispersion of thebrightener at a temperature below 75C, for example at room temperatureand then subjecting them to a dry heat treatment at a temperature above100 it being as a rule advisable previously to dry the fiber material ata moderately raised temperature, for example at at least 60C to about100C. the heat treatment in the dry state is then advantageouslyperformed at a temperature between 120 and 225C, for example by heatingin a drying chamber, ironing within the indicated temperature range orby treatment with dry, superheated steam. Alternatively, the dryingoperation and the dry heat treatment may be performed one immediatelysucceeding the other or simultaneously as one operation.

In the tables which follow later on, symbols have the followingsignificance:

Column I formula number Column 11 structural elements Column Ill crudeyield in Column IV recrystallisation medium, with these being designatedby the numbers listed below: 1 water, 2 ethanol, 3 dioxane, 4dimethylformamide, 5 tetrachlorethylene, 6 chlorobenzene, 7odichlorobenzene, 8 trichlorobenzene, 9 =toluene, 10 n-hexane, 1 1xylene.

Column V colour of the purified reaction of product, with the latterhaving been designated by the numbers listed below: 1 colourless, 2almost colourless, 3 pale green, 4 light green, 5 pale yellow, 6 lightyellow, 7 yellow, 8 pale greenish yellow, 9 light greenish yellow, 10greenish yellow.

Column VI melting point (uncorrected) in C. Column VII elementaryformula and analytical date (upper line calculated, lower line found).

The starting materials (or the methods for their preparation) to be usedfor preparing the compounds in the following examples are known in theart (see l-lelvetica Chimica Acta, Vol: 50, Fasc. 3, pages 946 to 957).

MANUFACTURING INSTRUCTIONS and 7.05 g of 4'-methoxybenzalaniline arestirred into 200 ml of anhydrous dimethylformamide with exclusion of airand treated all at once with l 1.2 g of potassium tertiary-butylate. Thecolour of the reaction mixture changes immediately from light beige tobluish violet and the temperature rises by a few C over the course of 2minutes. The mixture is stirred for a further 1 hour without externalwarming during which the temperature again drops somewhat. Thereafter400 ml of water are added dropwise at 10 to 15C and the reac-. tionmixture is filtered and washed with water until neutral.

The moist filter residue is now dissolved in 120 ml of dimethylformamidewith warming, treated with 25 ml of 10 percent strength hydrochloricacid and after a few minutes with 120 ml of water and cooled to about10C. After filtering, washing with water and methanol and subsequentdrying about 14.7 g, corresponding to percent of theory, of2,4-diphenyl-6-[4"-methoxystilbenyl-(4)]-1,3,5-triazine of formula areobtained in the form of a yellow powder of melting point 243.5 to246.5C. After chromatography in tetrachlorethylene on activatedaluminium oxide and recrystallisation from dioxane-ethanol, palegreenish yellow felted small needles of melting point 235.5C areobtained.

Analysis: C H ON (441,51) Calculated: C 81.61, H 5.25, N 9.52; found: C81.70, H 5.38, N 9.45.

B. 11.7 g of 2,4,6-tri-[4'-methylphenyl-(1')]-1,3,5- triazine of formulaand 18.1 g of benialaniline are stirred into 350 ml of anhydrousdimethylformamide with exclusion ,of air and treated all at once with28.0 g of potassium tertiary-butylate. The colour of the reactionmixture changes immediately from pale yellow to violet and thetemperature rises over the course of 5 minutes by about '10C. Themixture is stirred for a further 1% hours without external warming,during which the termperature again drops. Thereafter 350 ml of waterare added C, filtered off, and the residue first washed with water, thenwith methanol and dried. About 20.4 g, corre-- sponding to 99.5 percentof theory, of 2,4,6-tri- [sti1beny1-(4)]-1,3,5-triazine of formula 1 Ill N N are obtained in the form of light yellow very fine smallhydrochloric acid and a further 250 ml of water are needles which meltat 251 to 254C. After four recrystallisations from tetrachlorethylenewith the aid of Fullers earth light greenish yellow small needles ofmelting point 275 to 277C are obtained.

A'iifiysis; (1, 14, 81, (615.78). Calculated: (58177,?

triazine of formula 148), 18.1 g of benzalaniline and 12.6 g ofpotassium hydroxide powder containing about 10 percent water are stirredinto 300 ml of dimethylfonnamide with exclusion of air, in the course ofwhich a dark blue colour is produced after a few minutes. Thetemperature is raised to C over the course of 1 hour, and the mixturestirred for a further 4.0 minutes at this temperature and then cooled toabout 10C.

0 Now 611' ff water, mTof 10 percent strength successively addeddropwise at 10 to 20C. The precipitated reaction product is filteredoff, washed with water until neutral and freed of a by-product byfurther washing with methanol. After drying about 19.7 g, correspondingto 96.2- percent of theory, of 2,4,6-tri- [stilbenyl-(4)]-1,3,5-triazineof formula (149) are ob.- tained in the form of a yellow powder whichmelts at 262 to 267C. After chromatography in tetrachloreth- -ylene onactivated aluminum oxide and subsequently three recrystallisations fromtetrachlorethylene, light OCH:

are obtained in the form of a yellow powder of melting point 263.5 to265C. After chromatography in odichlorobenzene on activated aluminiumoxide and two recrystallisations from tetrachlorethylene yellow veryfine small needles of melting point 300C are obtained. 65

Analysis: C H O N (705.82). Calculated: C 81.68,H 5.57, N 5.95; found: C81.53, H 5.51, N 5.87. C. 1 1.7 g of 2,4,6-tri-[4'-methylphenyl-( 1')]-1,3,5-

293 to 293.5C are obtained.

is obtained, Yield: 93.1 percent of theory. Greenish yellow crystalsfrom odichlorobenzene. Melting point: 361 to 362C.

Analysis: C H N (844.67). Calculated: C 89.65, H 2

5.37, N 4.98;-found: C 89.74, H 5.28, N 5.10.

The following stilbenyl-1,3,5-triazine derivatives may be prepared in asimilar manner: From 2,4,6-tri-[4- methylphenyH l)-1,3,5-triazine offormula (148) and 4'-chlorobenzalaniline, the compound of formula Yield:98.5 percent of theory. Light yellow very fine needles fromtetrachlorethylene. Melting point: 284 to 285C.

i ll

Yield: 94.0 percent of theory. Light yellow very fine small needles fromtetrachlorethylene. Melting point: 315 to 317C.

Analysis: C H N Cl (719.12). Calculated: C 75.16, H 4.21, N 5.84; found:C 75.17, H 4.22, N 6.00. From 2,4-diphenyl-6-[4'-methylphenyl-( 1' ]-l,3,5-triazine of formula (146) and diphenyl-(4)-aldehyde-anil, thecompound of formula /N\ Inc- ([7 ffQ-CH:

N I 5H3 and diphenyl-(4)-aldehyde-anil, the compound of fordropwise. Theprecipitated'reac tion product is filtered mula I V g off, washed withwater until neutral and freed of a by- Yield: 100 percent of theory.Yellow very fine small product by further washing with 300 ml ofmethanol.

needles from xylene. Melting point: 162 to 162.5C. After drying about24.8 g, corresponding to 96.6 per- Analysis: C H N (886.16). Calculated:C 89.46, H cent of theory, of 2,4-di-[stilbenyl-(4) ]-6-phenyl- 5.80, N4.74; found: c 89.16, H 5.83, N 4.68. 30 l,3,5 triazine of formula I I37 g f 2 4 4' 1 are obtained as a light yellow powder. After chroma-(l)]-6-pheny1-1,3,5-triazine of formula tography in tetrachlorethyleneon activated aluminum 7 oxide and recrystallisation fromtetrachlorethylene practically colourless crystals of melting point 241to 241.5C are obtained. (28) N Analysis: C ,1-I ,N (513.61). Calculated:C 86.52, H

G C-QCH: 5.30, N 8.18; found: c 86.46, H 5.03, N 7.99.

The 1,3,5-triazine derivatives of formula c o [Melting point: 218 to218.5C], 18.1 g of benzalaniline and 50 g of potassium hydroxide powdercontaining about 10 percent water are stirred into 400 ml ofdimethylformamide with exclusion of air, during which a violet colour isproduced after a few minutes. The B: temperature is raised to 60C overthe course of 30 w .c. a.. minutes, and the mixture stirred for afurther 30 further at this temperature and then cooled to roomtemperature. Now 50 ml of water and 500 ml of 10 percent listed in thefollowing Table may be produced in a simistrength hydrochloric acid aresuccessively added lar manner.

I B] B: III IV V VI VII 30 Q lCH3 97-0 9/10 6 30-5-231 CnHa5Na -C-CH3 C,86.43 H, 6.19 N, 7.33 C, 86.33 H, 0.08 N, 7.56 CH3 31 Q Q 9 3 5 82405-241 CnHaiNa C, 87.58 H, 5.30 N, 7.13 C, 87.44 11, 5.55 N, 7-13 32 H9 7 9 5 w uNa C, 88.39 II. 5.30 N, 0.31 C, 88.33 H, 5.43 N, 0.28

63 Same as above (RH: 98. 3/2 10 325-328 O H H C-CH3 C, 38.18 H, 6.00 N,5.82 C, 88.37 H, 6.28 N, 5.80 CH:

34 .(10 Q 91- 7 7 2 359-350 ossHaaNa C, 89.04 H, 5.30 N, 5.66 C, 88.08H, 5.51 N, 5.73

E. 6.42 g of 4-[4-methyl-phenyl-(l)]-2,6-diphenylpyridine of formula 3.7g of benzalaniline and g of potassium hydroxide powder containing about10 percent of water are stirred into 150 ml of dimethylformamide withexclusion of air. The temperature is raised to 60C over the course of 30minutes, during which a violet colour develops. The reaction mixture isstirred for a further 30 minutes at 60 to 65C and then cooled to roomtemperature. Now 150 ml of water and 150 ml of 10 percent strengthhydrochloric acid are successively added dropwise, with cooling. Theprecipitated reaction product is filtered off, washed with a great dealof cold water and 400 ml of methanol, and dried. About 4.9 g,.corresponding to 59.8 percent of theory, of 4-[stilbenyl-(4')]-2,6-diphenyl-pyridine of formula are obtained in theform of a pale yellow powder which melts at 168 to 170C. Threerecrystallisations from dioxane-ethanol, with the aid of activatedcharcoal, yield colourless very fine crystals of melting point l77.5 to178C. Analysis: C31H23N (409.50). Calculated: C 90.92, H 5.66, N 3.42;found: C 90.98, H 5.84, N 3.35.

In a similar manner 4-[4-methyl-phenyl-(1)-]-2,6-

diphenyl-pyridine of formula (359), 4-phenyl-2,6-di- 4'-methyl-phenyl-(l ')]-pyridine of formula and 2,4,6-tr1-[4'-methyl-phenyl-(1')]-pyr1dmeof formula (38) out may be used to prepare the stilbenyl-pyridinederivatives of formula Q-VQ which are listed in the following table.

IV VI III CH=CH H Can nN CH=CH 77.1 /11 2 256-257 41 CH=CH H 71 21 we CC=CH CH=(I'JH OH=?H 93.8 5 2 194.5-195 43 e CH=CH -CH CasHnN N mcQc o -cmI c U CH3 W 9.] g of benzalaniline and 25 g of potassium hydroxidepowder containing about 10 percent of water reacted in 300 ml ofdimethylformamide according to the data -CH=CH of Example 30. About 9.9g, corresponding to 79.5 percent of theory, 2,4,6-tri-[stilbenyl-(4)I-pyrimidine of are obtained in the fonn of a light yellowpowder. After formula three recrystallisations from xylene with the aidof Fulas a pale-yellow powder which melts at 233234C. When the productisrecrystallized twice from aqueous dioxan, with the use of activecarbon, colourless, very fine crystals are obtained which melt at245246C.

Analysis: C l-1 N (439.53) calculated C 84.71 H .73 N 9.56% C 84.58 H5.87 N 9.82%

In a similar manner, the stilbenyll ,3,5-triazine derivative of theformula wr10=0110 p-0H=cu w (50) N on N (JH (1! 71-: w 0

listed in the following table. 0 01115 I n,w 1n v V VI VII 46 M 97.5 7/410 345-5347.5 co-i lsNz 0,131.18 11,5.50 N,3,32 0,9116 H,5.62 N,3,24

47 97.4 5/11 7 2ss-2ss.5 051mm,

0,111.07 11,5.27 N,3.66 0,111.05 H,5.38 N, 3.46

G. 12.1 g of stilbene-4-carboxylic acid chloride and 17.56 g ofpara-tolunitrile are stirred in 200 ml of dry ortho-dichlorobenzene. 6.6g of aluminium chloride are added and the temperature of the reactionmixture is adjusted to 1 15C once the exothermic reaction has subsided.5.3 g of ammonium chloride are added and the batch stirred for 20 hoursat 115C. After cooling, the reaction mixture is poured into much coldwater, washed neutral, freed from ortho-dichlorobenzene with steam, andan insoluble by-product removed by boiling with 1,500 ml ofdimethylformamide. The filtrate is diluted with 1,000 ml of water,cooled to room temperature, filtered with suction and dried. There areobtained about 12.8 g, corresponding to 58.6 percent of the theory, of2,4-di[4-methylphenyl-(1')]-6-stilbenzyl-(4)-1,3,5triazine of theformula can be prepared. Yield: 54.1 percent of the theoretical.Pale-yellow, fine crystal powder from aqueous dimethylformamide.

Melting point: 190 190.5C.

Analysis C H O N (483.54)

calculated: C 79.48 H 5.21 N 8.69%

found: C 79.43 H 5.50 N 8.56%

EXAMPLE 1 A polyester fabric (for example Dacron is padded at roomtemperature (about 20C) with an aqueous dis- EXAMPLE 2 100 Parts ofapolyestergranulate from terephthalic acid ethylene glycol polyester areintimately mixed 9 with 0.05 part of one of the stilbene derivatives ofthe formulae ([9), (21), (24), (25), (29), (30) to (34), (39), (41),(43), (45), (46) to (48) and melted at 285C while stirring. The spinningsolution gives much brightened polyester fibers when used for spinningthrough the usual spinnerets.

Alternatively, the aforementioned compounds may be added to the startingmaterial before or during polycondensation to form the polyester.

EXAMPLE 3 10,000 Parts of a polyamide in chip form prepared in knownmanner from hexamethylenediamine adipate are mixed in a tumbler for 12hours with 30 parts-of titanium dioxide (rutile modification) and 2parts of a compound of the formulae (19), (21), (24), (25), to I or(50). In a boiler heated to 300 to 310C with oil or diphenyl vapour, andin which the atmospheric oxygen has been replaced by superheated steam,the chips so treated are melted and stirred for half an hour. Under anitrogen pressure of atmospheres (gange), the melt is extruded through aspinneret and the resulting cooled filament wound on a bobbin. Thefilament obtained presents an excellent brightening effect.

We claim:

1. Process for the optical brightening of organic materials, whereinthere is incorporated in these materials or applied to their surfaces,0.00l-O.5 percent by weight of a compound of the formula in which arepresents hydrogen, halogen, the methyl group or the methoxy group, Zand Z each stands for a ring member =CH or =N- and a for a hydrogenatom, phenyl or a radical of the series in which (I) at least oneradical or differs from hydrogen or phenyl and has the significance ofone of the other radicals quoted for a, and in which (ll) terminalphenyl or naphthyl in said a substituents are unsubstituted orsubstituted by l to 3 C,C -alkyl groups, 1 to 2 halogen atoms, a C D-alkoxy group, a carboxylic acid, carboxylic acid ester or carboxylicacid amide group.

2. Process according to claim 1, wherein there is used a triazinederivative of the formula in B represents a phenyl or diphenyl and Bstands for hydrogen, phenyl or alkyl with l to 4 carbon atoms, and inwhich a terminal phenyl radical is unsubstituted or substituted by analkyl group with l to 4 carbon atoms, a halogen atom, a carboxylic acid,carboxylic acid ester, or carboxylic acid amide group or a methoxygroup.

3. Process according to claim 1, wherein there is used a compound of theformula N A7-]C \CAB N N in which A represents 5 QCH=CHQ3 is used inwhich V V or V each stands for l hydrogen, (2) unsubstituted styryl, (3)unsubstituted parais used in which W represents (1 phenyl, diphenyl,lnaphthyl or 2-naphthyl or (2) phenyl, diphenyl, lnaphthyl or Z-naphthylsubstituted by l to 3 C -C alkyl groups, 1 to 2 halogen atoms, a C C-alkoxy group, a carboxylic acid, carboxylic acid ester or car boxylicacid amide group.

6. Process according to claim 1, wherein a compound mentioned in sameclaim is incorporated in the material to be optically brightened beforesuch material is shaped.

7. Process according to claim I, wherein a compound mentioned in saidclaim is incorporated in a polycondensation product, prior to itsshaping or subsequently applied to its surface.

8. Process according to claim 7, wherein the polycondensation product isa synthetic polyamide or an arc- UNITED STATES PATENT AND TRADEMARKOFFICE CERTIFICATE OF CORRECTION PATENT NO. 3, +9 63 DATED November 19,197 i iNV ENTOR(S) ADOLF EMIL SIEGRIST ET AL it is certified that errorappears in the ab0ve-identified patent and that said Letters Patent arehereby corrected as shown below:

Column 2, left-hand portion of formula ie) should read:

Column 6, line il, after "hydroxide" delete the comma and substitute aperiod.

Column 7, line 38, "R -c N" should be R' -CEN Column l i, line 36, i)"should be i') Column 15, line 28, "(1' should be (1' Column 17, line 65,delete "30 further" and substitute 30 minutes Column 20, opposite "33"under "VII", "C H1 H should be 53 43 3 Column 21, middle-center portionof formula i i) should be UNITED STATES PATENT AND TRADEMARK OFFICECERTIFICATE OF CORRECTION PATENT NO. 3,8A9,1 63 Page 2 DATED November19, 197M INV ENTOR(S) ADOLF EMIL SIEGRIST ET AL It is certified thaterror appears in the above-identified patent and that said LettersPatent are hereby corrected as shown below:

Column 24, line H9, "C 79. 8" should be C 79.5 1

Column 25, line 66, "C -D should be C -Cq Signed and Scaled thistwenty-first D ay Of October I 9 75 [SEAL] A ttest:

RUTH C. MASON C. MARSHALL DANN Arresting Officer Commissioner of Patentsand Trademarks

1. PROCESS FOR THE OPTICAL BRIGHTENING OF ORGANIC MTERIALS, WHEREINTHERE IS INCORPORATED IN THESE MATERIALS OR APPLIED TO THEIR SURFACES,0.001-0.5 PERCENT BY WEIGHT OF A COMPOUND OF THE FORMULA
 2. Processaccording to claim 1, wherein there is used a triazine derivative of theformula
 3. Process according to claim 1, wherein there is used acompound of the formula
 4. Process according to claim 1, wherein apyridine derivative of the formula
 5. Process according to claim 1,wherein a pyrimidine derivative of the formula
 6. Process according toclaim 1, wherein a compound mentioned in same claim is incorporated inthe material to be optically brightened before such material is shaped.7. Process according to claim 1, wherein a compound mentioned in saidclaim is incorporated in a polycondensation product, prior to itsshaping or subsequently applied to its surface.
 8. Process according toclaim 7, wherein the polycondensation product is a synthetic polyamideor an aromatic polyester.